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21.
Microwave synthesis of nano-sized BaTiO3 and decrystallized titania, and microwave sintering of electroceramics including BaTiO3, Ba(Zn1/3Ta2/3)O3 (BZT), lead zirconate–titanate (i.e. Pb(Zr x Ti1?x )O3, or PZT), etc., as well as multilayer ceramic capacitors based on X7R, C0G, and ferrite multilayer chip inductors are presented. The results indicate that microwave processing significantly accelerated synthesis and sintering kinetics. As a result, processing time can be saved up to 90%, with the product properties comparable to or better than that of the conventional products.  相似文献   
22.
Abstract

The smaller capitals have larger levels of vehicular travel per head than the larger capitals and are more dependent on private transport, due mainly to greater non-work trip frequencies. Policy approaches are examined for reducing vehicular travel through increasing travel costs, changing land-use patterns and modifying people's values and attitudes to urban vehicular travel.  相似文献   
23.
Abstract

The paper considers economic effects of increased investment in public transport in Melbourne, based on investment plans of VicRail and the M.M.T.B. over a 5 year period, 1981–5. If the investment were to encourage a shift in patronage from private to public transport, this would change the magnitude of costs associated with passenger transport in Melbourne. Calculations are made of these possible cost savings, given particular levels of shift in patronage. The paper concludes by reviewing the feasibility of achieving given patronage changes.  相似文献   
24.
Landscape change occurs through the interaction of a multitude of natural and human driving forces at a range of organisational levels, with humans playing an increasingly dominant role in many regions of the world. Building on the current knowledge of the underlying drivers of landscape change, a conceptual framework of regional landscape change was developed which integrated population, economic and cultural values, policy and science/technology. Using the Southern Brigalow Belt biogeographic region of Queensland as a case study, the role of natural and human drivers in landscape change was investigated in four phases of settlement since 1840. The Brigalow Belt has experienced comparable rates of vegetation clearance over the past 50 years to areas of tropical deforestation. Economic factors were important during all phases of development, but the five regional drivers often acted in synergy. Environmental constraints played a significant role in slowing rates of change. Temporal trends of deforestation followed a sigmoidal curve, with initial slow change accelerating though the middle phases then slowing in recent times. Future landscape management needs to take account of the influence of all the components of the conceptual framework, at a range of organisational levels, if more ecologically sustainable outcomes are to be achieved.  相似文献   
25.
Studied the role of affect as a mediator of the overjustification effect and proposed that negative affect has a critical detrimental influence on intrinsic motivation, either as a reaction derived from self-perception and evaluation processes or as a factor that acts independently of these cognitive activities. Two studies, with 180 undergraduates, used the typical overjustification paradigm to test these hypotheses. In Exp I, the overjustification effect was successfully replicated for both behavioral and self-report measures of intrinsic motivation. It is important that the negative affect paralleled these results and was greatest in those conditions in which intrinsic motivation was predicted and found to be low (e.g., expected reward). In Exp II, affect was directly manipulated, independently of the cognitive manipulations. Results show that the induced positive affect erased the decrease in intrinsic motivation that was observed in Exp I. It is suggested that what determines the decrease in intrinsic interest in any activity is, in part, the amount of negative affect that becomes associated with the activity. (55 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
26.
The principal antibiotics formed by Streptomyces elizabethii have been isolated and identified as actinomycins IV and V, together with a methylpentaene macrolide, elizabethin, stereoisomeric with previously reported compounds.  相似文献   
27.
28.
Three new and two commercially available sugar matrices were comparatively evaluated for several fundamental properties of direct compression powder systems. These properties included: particle size distribution, powder flow (determined by a recording powder flow meter), bulk density and moisture content. The matrices studied were Dipac, Nutab, and California and Hawaiian (C & H) Products A, B, and C. These matrices were formulated in to chewable ascorbic acid, multivitamin, and antacid tablets, and analyzed for: weight uniformity, thickness, diameter, hardness, disintegration, resistance to impact stress, friability, dissolution and effect due to aging.

The data obtained showed that the new products (C & H products) were comparable, and in some cases, even superior to the commercially available ones.  相似文献   
29.
Abstract

This paper discusses the applicability of the ideas of fuzzy sets and grades of membership to problems encountered in the quantification of clinical (i.e., diagnostic and prognostic) judgment. The methods of constrained maximum likelihood are used to derive consensus estimates of grades of membership given a set of categorical data and an a priori set of specified pure types. A numerical example is given.  相似文献   
30.
This paper describes the main factors affecting the rapid prototyping of fine lattices by extrusion freeforming of powder, notably equipment accuracy, paste preparation, extrusion and post-processing and their effects on filament deposition and the defects that might be caused. Effective methods were devised in order to reduce the incidence of these defects. The results provide guidance for fabrication of very fine lattices from powder extrusion (comprising <100 μm diameter filaments) and improvement of sample quality.  相似文献   
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